.c-alpha
  position absolute
  top 0px
  right 0px
  bottom 0px
  left 0px
  .checkboard-wrap
    position absolute
    top 0px
    right 0px
    bottom 0px
    left 0px
    overflow hidden
  .gradient
    position absolute
    top 0px
    right 0px
    bottom 0px
    left 0px
  .container
    position relative
    z-index 2
    height 100%
    margin 0 3px
  .pointer
    z-index 2
    position absolute
  .picker
    width 4px
    border-radius 1px
    height 8px
    box-shadow 0 0 2px rgba(0, 0, 0, .6)
    background #fff
    margin-top 1px
    transform translateX(-2px)